2,730 research outputs found

    Physiological Functions of the COPI Complex in Higher Plants

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    COPI vesicles are essential to the retrograde transport of proteins in the early secretory pathway. The COPI coatomer complex consists of seven subunits, termed alpha-, beta-, beta'-, gamma-, delta-, epsilon-, and zeta-COP, in yeast and mammals. Plant genomes have homologs of these subunits, but the essentiality of their cellular functions has hampered the functional characterization of the subunit genes in plants. Here we have employed virus-induced gene silencing (VIGS) and dexamethasone (DEX)-inducible RNAI of the COPI subunit genes to study the in vivo functions of the COPI coatomer complex in plants. The beta'-, gamma-, and delta-COP subunits localized to the Golgi as GFP-fusion proteins and interacted with each other in the Golgi. Silencing of beta'-, gamma-, and delta-COP by VIGS resulted in growth arrest and acute plant death in Nicotiana benthamiana, with the affected leaf cells exhibiting morphological markers of programmed cell death. Depletion of the COPI subunits resulted in disruption of the Golgi structure and accumulation of autolysosome-like structures in earlier stages of gene silencing. In tobacco BY-2 cells, DEX-inducible RNAi of beta'-COP caused aberrant cell plate formation during cytokinesis. Collectively, these results suggest that COPI vesicles are essential to plant growth and survival by maintaining the Golgi apparatus and modulating cell plate formation.1196Ysciescopu

    Using WhatsApp Focus Group Discussions to Collect Qualitative Data Collection During a Pandemic: Exploring Knowledge, Attitudes, and Perceptions of COVID-19 in Singapore

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    This qualitative study aimed to explore Singapore residents’ knowledge, attitudes, perceptions, and behaviors around COVID-19 as shaped by different information sources. Through utilizing WhatsApp as a means of conducting digital focus group discussions (FGDs), participants were involved in five consecutive days of discussions through both synchronous and asynchronous means. We found that the use of WhatsApp as a means of conducting FGDs not only served as a means of generating essential, time-sensitive data in the community, but also advanced the quality and quantity of data generated, democratized, and enhanced the participatory nature of FGDs, and facilitated the communication of potential issues around data privacy between facilitators and participants. Although challenges around privacy and confidentiality remain, this means of collecting data is novel in terms of providing timely and relevant data during a pandemic and would be appropriate to be further utilized in the context of other health-related research beyond a public health emergency

    Fracture Liaison Service and Its Role in Secondary Fracture Prevention in Malaysia: A Scoping Review

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    Introduction: Fragility fractures, which occur after a low- trauma injury, increases with advancing age. Such fracture doubles the life-time risk of sustaining another fracture. This risk is highest in the immediate 18 months after the index fracture. However, most patients do not receive the appropriate risk assessment and intervention to reduce this risk. A coordinated model of care termed Fracture Liaison Service (FLS) has been reported to address this treatment gap. Materials and methods: This scoping review aims to explore the potential role and delivery of FLS services in Malaysia. Scientific and non-scientific sources relevant to FLS were identified from electronic bibliographic databases, specialist journals and relevant websites. Findings were categorised into themes and presented narratively. Results: FLS services remain concentrated in the Klang Valley. Even within FLS services, many do not have extensive coverage to risk assess all fracture patients. These services are multidisciplinary in nature where there are links between different departments, such as orthopaedics, osteoporosis expertise, bone densitometry, rehabilitation, falls services and primary care. FLS was able to increase the number of people undergoing fracture risk assessment and treatment. The importance of FLS was highlighted by local experts and stakeholders. Its implementation and delivery are supported by a number of national guidelines. Conclusion: FLS is central to our national efforts to reduce the impending fragility fracture crisis in the coming years. Continued effort is needed to increase coverage within FLS services and across the country. Training, awareness of the problem, research, and policy change will support this endeavour

    A dual protein expression system in Bacillus subtilis

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    We have developed a dual expression system for the simultaneous overexpression of two proteins in Bacillus subtilis. Two candidate genes, xylanase (xynA) and glucanase (bglS) from B. subtilis strain 168, which were engineered with independent Shine-Dalgarno (SD) sequences, were cloned in tandem into a transfer vector, which was then transformed into B. subtilis strain 1A304 (φ105MU331). The genes were under the transcriptional control of a strong promoter of a bacteriophage, φ105, where transcription was initiated upon thermal induction. Six constructs were made to compare the factors that affected the yields of the gene products. The expression level of each candidate gene was found to correspond to its position relative to the phage promoter, irrespective of the identity of the insert. The lower expression level of the second insert might have been due to limited resources for protein synthesis, a short half-life of the mRNA, or an early termination of the RNA polymerase. Curiously, gene duplications in tandem did not lead to further increase in production. © 2002 Elsevier Science (USA). All rights reserved.postprin

    A Novel Genome-Wide Association Study Approach Using Genotyping by Exome Sequencing Leads to the Identification of a Primary Open Angle Glaucoma Associated Inversion Disrupting ADAMTS17

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    Closed breeding populations in the dog in conjunction with advances in gene mapping and sequencing techniques facilitate mapping of autosomal recessive diseases and identification of novel disease-causing variants, often using unorthodox experimental designs. In our investigation we demonstrate successful mapping of the locus for primary open angle glaucoma in the Petit Basset Griffon Vendéen dog breed with 12 cases and 12 controls, using a novel genotyping by exome sequencing approach. The resulting genome-wide association signal was followed up by genome sequencing of an individual case, leading to the identification of an inversion with a breakpoint disrupting the ADAMTS17 gene. Genotyping of additional controls and expression analysis provide strong evidence that the inversion is disease causing. Evidence of cryptic splicing resulting in novel exon transcription as a consequence of the inversion in ADAMTS17 is identified through RNAseq experiments. This investigation demonstrates how a novel genotyping by exome sequencing approach can be used to map an autosomal recessive disorder in the dog, with the use of genome sequencing to facilitate identification of a disease-associated variant

    Atopic dermatitis, cutaneous steroids and cataracts in children: two case reports

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    <p>Abstract</p> <p>Introduction</p> <p>Atopic dermatitis is a chronic, pruritic, eczematous skin disease mediated through an immediate (type I) hypersensitivity reaction. Posterior sub-capsular cataracts are a recognised complication of atopic dermatitis in adults; however they are rare in children. The management of atopic dermatitis is based on the exclusion of allergens, the use of emollients, and on topical corticosteroids for disease exacerbations. Cataracts may be due to atopic dermatitis but may also occur secondary to the use of corticosteroids.</p> <p>Case presentation</p> <p>We describe two children with atopic dermatitis, treated with cutaneous corticosteroids, both of whom were diagnosed with bilateral posterior sub-capsular cataracts.</p> <p>Conclusion</p> <p>These cases demonstrate that atopic dermatitis and topical corticosteroids may be associated with cataracts in children as well as adults. The cause of cataracts in atopic dermatitis is not known, however, it has been suggested that habitual tapping and rubbing of the face may play a role. Care needs to be taken when prescribing corticosteroids. Inadequate treatment of atopic dermatitis may lead to other ocular complications such as keratitis and permanent visual loss.</p

    r.hu-Erythropoietin (EPO) treatment of pre-ESRD patients slows the rate of progression of renal decline

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    BACKGROUND: As EPO treatment of chronic anemia of advanced renal disease is now the standard of care we examined if such treatment may slow the progression of renal function decline. METHODS: Data of 18 pre-ESRD patients were analyzed retrospectively 12 months prior and prospectively 12 months after the initiation of EPO. Mean creatinine was 5.0 ± 1.8 mg/dL (Mean ± SEM) when starting EPO at a weekly dose of 5000 ± 500 units once the hematocrit was below 30 %. EPO dose was titrated monthly for a hematocrit between 33.0% and 37.0%. Metabolic complications and hypertension were controlled. RESULTS: At month_0 the average blood pressure was 148/76 ± 5/4 mmHg and at month_12 it was 145/73 ± 6/3 mmHg (p = 0.75 by 2 tailed paired Student's t test). 12/18 patients were on an ACE-i or ARB before month_0 and 14/18 were on it after (p = 0.71 by Fisher's 2 tailed exact test). The average hematocrit rose from 26.9% ± 0.6 to 33.1 % ± 0.1. When linear regression analysis was applied to pre- and post-EPO 1/creatinine data the mean rate of decline was -0.0140 ± 0.0119 (mean ± SD) and -0.0017 ± 0.0090 (non-parametric Wilcoxon matched pairs signed rank sum test: Z value: -2.91; P = 0.004) respectively. 5/18 patients did not require dialysis 12 months after starting EPO (month_0). CONCLUSION: Treatment of the anemia of chronic renal failure with erythropoietin, when instituted together with vigorous metabolic control may slow the rate of renal function decline
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